Q: what causes a P0174 bank2 combustion too lean

asked by on June 19, 2016

I have a 2000 ford explorer 4.0 sohc and here lately when driving sumtimes outta nowhere itll just lose speed and the rpms drop,doesnt wanna go anywhere it seems..until i pull over n rurn truck off then on again and its ok for a little bit then will do it again. I took it to autozone to have the codes pulled cause yes my check enginelight is on and they got the code P0174-bank 2 conbcombustion is too lean. I changed the bank 2 oxygen censor and cleaned my MAF censor and it still does it. What else could it be??

My car has 164000 miles.

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You will need to have the system inspected thoroughly to see why the vehicle is going lean. The possible causes are that you are loosing fuel pressure or fuel volume. If fuel pressure gets too low it will cause the loss of power and the fuel filter may cause the loss of fuel volume if it is clogged.

The O2 sensor is just letting you know that it detected a lean condition and there are several tests that would need to be done to isolate the problem. You may have an injector on bank two going bad or have a computer going bad.

All of these possibilities would need proper diagnosis to isolate the problem. I’d recommend getting some help from a professional mechanic who can diagnose your Check Engine Light and make the necessary repairs to get your car running normally again.

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